Dissertation Research: The Effects of Population Bottlenecks on Genetic Diversity and Rates of Molecular Evolution in Spheniscus Penguins

0073177Fleischer Pincus由于人类活动，许多物种目前正在经历人口规模的急剧减少。 这种减少被称为“人口瓶颈”，使人口遭受多种危害。 这些风险包括短期的人口风险，如疾病或自然灾害，以及小尺寸的长期遗传效应，如近亲繁殖造成的变异损失。 企鹅属Spheniscus是研究种群瓶颈的遗传效应的合适系统，因为它包括两种经历过重复瓶颈事件的濒危企鹅（加拉帕戈斯企鹅，洪堡企鹅）和两种没有经历过这些波动的企鹅（麦哲伦企鹅，非洲企鹅）。 这些瓶颈是由厄尔尼诺事件期间的人为影响和环境变化造成的，厄尔尼诺事件可使人口减少77%。 本计画提出利用分子遗传学技术比较遗传变异，以验证瓶颈理论。 这项研究不会伤害企鹅，每只鸟只需要几滴血或一根羽毛就足够了。了解瓶颈事件对小种群的影响可能对它们的长期生存至关重要。 遗传变异对于未来的进化潜力和种群的持久性是必要的。 本研究将直接比较企鹅种群波动对种群稳定性的影响。 这一结果可能对许多濒危物种的保护有直接价值。

0073177Fleischer & PincusMany species are currently undergoing drastic reductions in population size due to human activities. Such reductions, termed "population bottlenecks", subject populations to multiple hazards. These include both short-term demographic risks, such as a disease or natural disaster, and long term genetic effects of small size, like loss of variation due to inbreeding. The penguin genus Spheniscus is an appropriate system for studying the genetic effects of population bottlenecks because it comprises two endangered species of penguin that have undergone repeated bottleneck events (Galapagos Penguin, Humboldt Penguin), and two species that have not undergone these fluctuations (Magellanic Penguin, African Penguin). The bottlenecks are caused by both anthropogenic impacts and environmental changes during El Nino events, which can reduce populations by up to 77%. This project proposes to test bottleneck theories by comparing genetic variation using molecular genetic techniques. This research will not harm penguins; only a few drops of blood or one feather from each bird is sufficient.An understanding of the effects of bottleneck events on small populations may be critical to their long-term survival. Genetic variation is necessary for future evolutionary potential and population persistence. This study will directly compare the genetic effects of population fluctuations to population stability using the penguin genus Spheniscus. The results may be of direct value to the conservation of many endangered species.